A conventional bag inflated with air is shown in FIGS. 1 and 2. The inflatable bag comprises a bag member 1 including two PE (polyethylene) films 10 and two nylon films 12 each formed on the PE film 10. For making the surface of the bag member 1 glossy, some manufacturers of the art may plate an aluminum layer 14 on an inner surface of each nylon film 12 (i.e., the surface facing the PE film 10). Next, press the nylon films 12 having plated aluminum layers 14 onto the PE films 10 to finish the inflatable bag. As an end, the surface of the bag member 1 looks glossy.
For facilitating air inflation, it is typical of providing an air valve 2 in the PE films 10 in which a portion of the air valve 2 is concealed in the PE films 10 and a remaining portion thereof is projected from the PE films 10. For forming the bag member 1, outer surfaces of the PE films 10, an outer surface of the air valve 2, and corresponding inner surfaces of the PE films 10 are subjected to heat for sealing. At the same time, a flat channel 20 is formed in the air valve 2. Also, ink 20 is coated on engaged inner surfaces of the channel 20.
For inflating the inflatable bag, a user has to insert one end of an elongate charging tube (not shown) through the air valve 2 into the bag member 1. Next, the user may blow the other end of the charging tube for inflating the bag member 1 or an air compressor is employed to blow same. The user may pull the charging tube out of the air valve 2 after inflating the inflatable bag. At this time, air pressure in the bag member 1 is higher than the atmospheric pressure and thus may tightly compress the flat channel 20 in the bag member 1 for sealing. At the same time, ink 22 coated on inner surfaces of the channel 20 is mixed to prevent air from leaking. Next, the user may tie a projected portion of the air valve 2 around a support of a post such that the bag member 1 may be affixed to the support for exhibition.
However, a pattern 18 on the bag member 1 is formed by printing on the surface thereof by the manufacturer in advance because the surface of the bag member 1 is formed of nylon film 12. A customer has to select an inflatable bag having a preferred pattern 18 printed thereon or an appropriate one from a number of inflatable bags with different patterns 18 produced by the manufacturer in advance. Thus, the number of inflatable bags, which can be selected by a customer, is limitedly provided by the manufacturer. In another case some customers may select to give up buying the inflatable bag(s) because no inflatable bag has preferred pattern, resulting in a sales loss of inflatable bag vendor. Moreover, most patterns printed on the inflatable bags are dull without inventive concept and they are misaligned with the trend of emphasizing personal preference and novelty. Thus, it is desirable to provide a novel inflatable bag having a pattern printed according to personal preferred design rather than produced by the manufacturer in advance in order to overcome the inadequacy of the prior art.